Overview
G2b2 represents the eastern half of the G2b radiation, forming a lineage that is clearly centered around Iran, Afghanistan, Pakistan and the western Indian subcontinent. Its downstream signatures appear frequently among Pakistani and Afghan ethnic groups—especially those with deep mountain or highland roots—indicating multiple ancient founder effects. Compared to G2b1, G2b2 shows stronger representation across South Asia and less presence in the western Iranian Plateau.
G2b2 did not participate in Neolithic farming expansions and instead reflects localized demographic histories in the Iranian Plateau and the Hindu Kush corridor. These regions served as refugia and crossroads for early Holocene pastoral and agro-pastoral societies.
Geographic distribution
G2b2 reaches its highest prevalence in Pakistan (particularly among Pashtun, Baloch, and Kalash groups), Afghanistan, northwestern India and occasionally in Tajikistan. Moderate frequencies appear in southeastern Iran and Baluchistan. Minimal presence is detected in the Gulf region and the Caucasus, reflecting historical migration rather than ancient continuity.
Its pattern maps closely onto highland–foothill ecotones stretching from eastern Iran through Afghanistan and into Pakistan.
Ancient DNA
- No fully confirmed ancient G2b2 samples exist due to low sampling density in South-Central Asia, but prehistoric remains from Bactria and the Hindu Kush show upstream SNP affinities.
- Iron Age individuals from eastern Iran exhibit markers potentially ancestral to G2b2 lineages.
- The absence of G2b2 in Near Eastern and European Neolithic contexts confirms its localized eastern Holocene history.
Phylogeny & subclades
G2b2 divides into a small number of downstream clusters, including Baluchistan-focused branches, Afghan tribal lineages and scattered Indo-Afghan microclades. Its topology shows a pattern of repeated founder effects, consistent with geography and social structure in the highland zones of eastern Iran and the Hindu Kush.
- G2b2* basal
- Baluchistan-centered branches
- Hindu Kush microclades
- Pakistan/Afghanistan founder lineages
Notes & context
G2b2 is an important but understudied lineage that provides unique insight into early Holocene demographic processes in South-Central Asia. It also highlights how geographically challenging landscapes preserved deeply diverged paternal lines.
References & external links